I think 1KV would be ok to check for moisture. To be rid of any ambiguity, I would go to at least 3~5 KV. You can figure on being overrated for the service. Let's face it, most of your finals will run upwards to around 3.5 KV unless you got 4-1's X 4-1's. With that kind of rating, you are in your ballpark. Mod-U-Lator, Mike(y) W3SLK ----- Original Message ----- From: "Mark Foltarz" <[EMAIL PROTECTED]> To: "Discussion of AM Radio in the Amateur Service" <[email protected]> Sent: Thursday, September 21, 2006 1:38 AM Subject: Re: [AMRadio] Seeking advice on testing modulation transformers
Mike, I have seen some less expensive meggers out there with voltage output @ 1 kV and a resistance range of 1 Gohm. I know the resistance scale is right. I suspect the voltage although about half of what it might be will probably produce good results. Do you suppose a 1 KV megger would do the trick? Mark --- Mike Sawyer <[EMAIL PROTECTED]> wrote: > Mark, > I have found that the best way to check a transformer is to use a HI > Pot > tester or an insulation tester like a megger with about 5kv capability. > I'm > fortunate to have access to a 5KV jobber at work. Anything less than 500K > ohms would be suspect. > You could go to Rich Measures webpage. I believe he has a neat schematic > for > HI pot testing tubes which would accomplish the same thing. > Mod-U-Lator, > Mike(y) > W3SLK > ----- Original Message ----- > From: "Mark Foltarz" <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Wednesday, September 20, 2006 6:53 PM > Subject: [AMRadio] Seeking advice on testing modulation transformers > > > I am sure the following has happened to all of us. > > You build a transmitter or modulator using a transformer that you have > had > around for years. > > You then apply power only to find a short to case or worse on the > cherished > modulation transformer. > > Well, I would like to avoid that with several chunks o' iron I have > here. > > Specifically, I have the big Thordarson multimatch, a pair of those RCA > 5500 > : 5500 surplus units, and a mod transformer from a BC610E. > > I was thinking of applying power between case and a terminal and looking > for > leakage. > > In the past I have even run a mod transformer with a case leakage on a > piece > phenolic with favorable results. > > By the way, does anyone have any experience using the RCA 5500 5500 > units? > > TNX > > de KA4JVY > > Mark > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com > ______________________________________________________________ > AMRadio mailing list > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Partner Website: http://www.amfone.net > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] > > ______________________________________________________________ > AMRadio mailing list > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Partner Website: http://www.amfone.net > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ______________________________________________________________ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] ______________________________________________________________ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected]
